In #31614, I added an unfocus() to FocusNodes to allow giving up of focus, but it only worked on the primary focus. This changes that so that it will unfocus the entire chain, not just the primary focus. Now, if you call unfocus() on a FocusNode or FocusScopeNode, and their hasFocus returns true, then after calling unfocus(), it will return false. Before this change, it would only do that if hasPrimaryFocus was also true.

This also fixes a bug in the way setFirstFocus was implemented, making it conform more to the behavior of the previous implementation. It has simplified logic in reparent, and in when it requests focus for scope nodes that have had setFirstFocus called on them.

Make FlutterError objects more structured so they can be displayed better in debugging tools such as Dart DevTools.

https://github.com/flutter/engine/compare/8768180a8871...6280d4266983

git log 8768180a8871ede2af9d483d764109b92df6faf9..6280d4266983ff8eff24f26164d10172e3824385 --no-merges --oneline
6280d4266 Dart SDK roll for 2019-04-30 (flutter/engine#8796)
c67870cfd Roll src/third_party/skia 08c79d61450b..6c8f5b31ac49 (4 commits) (flutter/engine#8799)

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* Introduce BottomSheetTheme and shape support for bottom sheet

* Add bottom sheet theme to ThemeData. Use theme in bottom sheet build

* Expose color, elevation, shape to showModalBottomSheet helper

* Expose color, elevation, shape to showBottomSheet helper

* Address PR feedback

* Address PR feedback

* Address additional PR feedback

This reverts commit fea2c7d6.

8768180a8 Roll src/third_party/skia e6a83e160860..08c79d61450b (1 commits) (flutter/engine#8797) (#31887)


https://github.com/flutter/engine/compare/2f11d3c4a205...8768180a8871

git log 2f11d3c4a205eca899de19617303ca8174ada7e3..8768180a8871ede2af9d483d764109b92df6faf9 --no-merges --oneline
8768180a8 Roll src/third_party/skia e6a83e160860..08c79d61450b (1 commits) (flutter/engine#8797)

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Show appropriate error message when fonts isn't iterable

This reverts commit c0d5fd23.

https://github.com/flutter/engine/compare/f2d21795be43...2f11d3c4a205

git log f2d21795be43aa4f596b75668b772a97af3888a9..2f11d3c4a205eca899de19617303ca8174ada7e3 --no-merges --oneline
2f11d3c4a Roll src/third_party/skia f808c5e3afa3..e6a83e160860 (3 commits) (flutter/engine#8795)
1219e5c7d Re-create texture from pixel buffer onGrContextCreate (flutter/engine#8792)

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https://github.com/flutter/engine/compare/59b91392e20a...f2d21795be43

git log 59b91392e20ac6b397bb4e257dc08333c54658c9..f2d21795be43aa4f596b75668b772a97af3888a9 --no-merges --oneline
f2d21795b Roll buildroot to pull in Fuchsia SDK related updates. (flutter/engine#8793)
5e5705000 Roll src/third_party/skia 836ff5e40560..f808c5e3afa3 (11 commits) (flutter/engine#8791)
5a9e87457 Roll src/third_party/skia 494aa3db9e78..836ff5e40560 (2 commits) (flutter/engine#8788)

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* Allow DSS to be dragged when its children do not fill extent

* Fix when maxChildSize  < 1.0

This will fix our flutter build post-submit analyze test

Merge on red to fix flutter build

* Revert "Revert "Add buttons to gestures (#30339)" (#31801)"

This reverts commit 8fd7fa49.

* Synthesise kPrimaryButton for unknown devices

* Change TestPointer to a better API

This reverts commit 120a1fc4.

Updated the golden file

## Description

Make `_RenderCustomClip`'s `clipBehavior` non-final so we can update it during `updateRenderObject`. This will support `clipBehavior` changes in hot reload.

## Related Issues

Fixes #30863

## Tests

I added the following tests:

* ClipRect updates clipBehavior in updateRenderObject
* ClipRRect updates clipBehavior in updateRenderObject
* ClipOval updates clipBehavior in updateRenderObject
* ClipPath updates clipBehavior in updateRenderObject
* PhysicalModel updates clipBehavior in updateRenderObject
* PhysicalShape updates clipBehavior in updateRenderObject

59b91392e Roll src/third_party/skia a6d723f32f32..494aa3db9e78 (1 commits) (flutter/engine#8787) (#31847)


https://github.com/flutter/engine/compare/64b1d38081c2...59b91392e20a

git log 64b1d38081c2eadfc555da99bbdb3a1ec2c49a13..59b91392e20ac6b397bb4e257dc08333c54658c9 --no-merges --oneline
59b91392e Roll src/third_party/skia a6d723f32f32..494aa3db9e78 (1 commits) (flutter/engine#8787)

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64b1d3808 Roll src/third_party/skia 79e53712a05f..a6d723f32f32 (3 commits) (flutter/engine#8785) (#31830)


https://github.com/flutter/engine/compare/c0036315d4ca...64b1d38081c2

git log c0036315d4caed8db3ae2adb66aaedd6466fddf7..64b1d38081c2eadfc555da99bbdb3a1ec2c49a13 --no-merges --oneline
64b1d3808 Roll src/third_party/skia 79e53712a05f..a6d723f32f32 (3 commits) (flutter/engine#8785)

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Fixes a typo in the key generator readme.

Updated the examples in the readme to reflect that the examples were for physical key codes, where we're actually talking about logical key codes there.

https://github.com/flutter/engine/compare/1ecf924ff861...c0036315d4ca

git log 1ecf924ff86146c09ce834b295a2c4446122857c..c0036315d4caed8db3ae2adb66aaedd6466fddf7 --no-merges --oneline
c0036315d Roll src/third_party/skia bd425405f3aa..79e53712a05f (3 commits) (flutter/engine#8783)
5aa5b6cbf VirtualDisplay size constraint - add a comment explaining the reason (flutter/engine#8780)
ee3f04ac8 Roll src/third_party/skia 037884e5080b..bd425405f3aa (3 commits) (flutter/engine#8781)
ab01d7396 Roll src/third_party/skia d425dee662d1..037884e5080b (10 commits) (flutter/engine#8778)
a0bb23aad Fix header include guards for fml/thread_local.h (flutter/engine#8721)

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- Move `setState` to only be invoked when guarded by `widget._allowMultiplePanelsOpen`, fixing the case for `ExpansionPanelList`

- Remove setting `_currentOpenPanel` to `widget.initialOpenPanelValue` in `didUpdateWidget`, since this should only occur on `initState` and not every time the widget is updated. This fixes the problem for `ExpansionPanelList.radio`

- Added a `didUpdateWidget` condition for when `ExpansionPanelList` changes into `ExpansionPanelList.radio` to open the panel at `widget.initialOpenPanelValue`

- Added test cases for regression, expansionCallback cases, and `didUpdateWidget` transitions between `ExpansionPanelList` and `ExpansionPanelList.radio`

* Re-enable const

This reverts commit 727e7e82.

## Description

As we've introduced offset to the Opacity layer, we have to override
`applyTransform` to make Leader/FollowerLayer work correctly.

## Related Issues

Fixes https://github.com/flutter/flutter/issues/30587

Together with https://github.com/flutter/engine/pull/8585,
this test will also exercise test against
https://github.com/flutter/flutter/issues/30586.

## Tests

I added the following tests:
* text field selection toolbar renders correctly inside opacity

* Callbacks of tap, long press, drag, and double tap GR respond to only primary events.
* Add "secondary" callbacks to tap.
* Recognizers only compete on events if there are any related callbacks.
* Add "kSecondaryButton" constant.